Abnormalities of cholesterol and fatty acid homeostasis, that are reflected as diverse dyslipidemias, are causal of atherosclerosis and consequently cardiovascular disease (CVD). This disease is one of the major health problems in industrialized countries and is reaching the same prevalence in adults in developing nations. Most studies show that statins reduce low density lipoproteins (LDL) cholesterol by 25-30% and the relative risk of coronary events by approximately 30%. While this beneficial effect is significant, effectively 70% of the treated cohort remains with unchanged risk. This has prompted intense research in order to identify other common abnormalities of lipid metabolism that if efficiently treated could improve the results of current CVD therapy.
The nuclear hormone receptors LXR α and β use oxysterols as natural ligands. They appear to act as cholesterol sensors with target genes that are required for cholesterol efflux from macrophages, like ATP binding cassette transporter A1 (ABCA1) and apoE, as well as gene products, like cholesterol ester transferase protein (CETP) and phospholipid transport protein (PLTP), that are required for the function of high density lipoprotein (HDL) in the reverse cholesterol transport. In the liver, LXR ligands seem to stimulate the hepatobiliary secretion of cholesterol, a pathway controlled by the ABCG5 and ABCG8. The same cholesterol transporters appear to reduce cholesterol absorption in enterocytes, therefore influencing total body cholesterol balance. These effects of LXR stimulation could help to explain its remarkable anti-atherosclerotic properties observed in animal models.
Recently the synthetic LXR ligands GW3965 (Glaxo) and T-0901317 (Tularik) were reported to increase glucose tolerance in fat fed obese mouse, which was interpreted to result from reduced hepatic gluconeogenesis and increased glucose uptake in adipocytes Lafitte B A et al. (Proc Natl Acad Sci USA. 2003 Apr. 29; 100(9):5419-24). Activation of LXR's improves glucose tolerance through coordinated regulation of glucose metabolism in liver and adipose tissue.
JP2001163786A discloses the synthesis of certain novel 2-(substituted alkyl)-4-(substituent)-5-(substituent)isothiazol-3(2H)-one 1,1-dioxides wherein the 4- or 5-positions are substituted by e.g. H, lower alkyl or carboxyl. These compounds are reported to have matrixmetalloproteinase (MMP) inhibitory activity (especially matrixmetalloproteinase-13 (MMP-13) inhibitory activity) and aggrecanase inhibitory activity, and are useful in the prevention or treatment of arthritis (especially osteoarthritis) and for inhibiting metastasis, infiltration or proliferation of cancer (especially breast cancer).
EP1069110A1 discloses the synthesis of certain novel 2-(substituted alkyl)-4-(substituent)-5-(substituent)isothiazol-3(2H)-one 1,1-dioxides wherein the 4- or 5-positions are substituted by e.g. H, lower alkyl or carboxyl. These compounds are reported to have matrixmetalloproteinase-13 (MMP-13) inhibitory activity and aglycanase inhibitory activity, and are useful for treating arthritic disorders such as reumatoid arthritis.
WO9708143A1 discloses the synthesis of 2-(substituted alkyl)-4-(substituent)-5-(substituent)isothiazol-3(2H)-one 1,1-dioxides wherein the substituents in 4- or 5-positions are selectioned from nitro, cyano, trifluoromethyl, carbethoxy, carbomethoxy, carbopropoxy, acetyl, carbamoyl, carbamoyl substituted with an alkyl of 1 to 3 carbon atoms, acetoxy, carboxy, hydroxy, amino, amino substituted with an alkyl of 1 to 3 carbon atoms, alkyl of 1 to 4 carbon atoms, alkoxy of 1 to 4 carbon atoms or halo, or the 4 and/or 5 positions are unsubstituted, and their use for reducing levels of Tumor Necrosis Factor (TNF) in mammals.
In the application WO05/005417 it is disclosed that certain novel 1-(substituted alkyl)-3 amino-4 phenyl-1H-pyrrole-2,5-dione derivatives have utility in the modulation of nuclear hormone receptors Liver X Receptor (LXR) α (NR1H3) and/or β (NR1H2) and in treating and/or preventing clinical conditions including cardiovascular diseases.
In the application WO05/005416 it is disclosed that certain novel 5-thioxo-1,5-dihydro-2H-pyrrol-2-one and 1H-pyrrole-2,5-dithione derivatives have utility in the modulation of nuclear hormone receptors Liver X Receptor (LXR) α (NR1H3) and/or β (NR1H2) and in treating and/or preventing clinical conditions including cardiovascular diseases.
WO05/035551 discloses certain novel 2-(substituent)-4-(substituent)-5-(substituent)isothiazol-3(2H)-one 1,1-dioxides. These compounds are reported to modulate the activity of a target protein such as a phosphatase.
The term “LXR modulator” as used herein more specifically means a compound with the ability to modulate the biological activity of LXRα and/or LXRβ via increase or decrease of the function and/or expression of LXRα and/or LXRβ, where LXRα and/or LXRβ function may include transcription regulatory activity and/or protein-binding. Modulation may occur in vitro or in vivo. Modulation, as described herein, includes antagonism, agonism, partial antagonism and/or partial agonism of a function or characteristic associated with LXRα and/or LXRβ, either directly or indirectly, and/or the upregulation or downregulation of LXRα and/or LXRβ expression, either directly or indirectly. More specifically, such an LXR modulator either enhances or inhibits the biological activities of LXR via the function and/or expression of LXR. If such a modulator partially or completely enhances the biological activities of LXR via the function and/or expression of LXR, it is a partial or full LXR agonist, respectively. It is the object of the present invention to provide LXR modulators. Another object of this invention is to provide LXR modulator compounds being LXR agonists.
It should be noted that to show activity in the specific Test Methods described herein, the LXR modulator compound must bind to the ligand binding domain of the LXR and recruit either the specific peptide derived from the co-activator protein, SRC1, to the modulator compound-bound LXR complex in the described Co-activator recruitment assay, or one or more of the nuclear hormone receptor co-factors present in for example the U2OS cell-based method described herein. The compounds of this invention that form an LXR-modulator compound-complex may recruit at least one or more of the other >80 known different nuclear hormone receptor cofactors in any other cell-based method prepared and assayed according to known procedures. Compounds according to formula (I), that do not recruit the SRC1-derived peptide or any of the co-factors present in the in cell-based method described herein, is however anticipated to bind to LXR and the LXR-modulator compound-complex so formed will recruit at least one or more of the other >80 known different nuclear receptor cofactors present in other cellular system. The LXR modulator compound-complex may also displace co-repressors, such as NcOR, with simultaneous recruitment of a co-activator or may only displace a co-repressor without co-activator recruitment, leading to partial activation of certain LXR regulated genes. Recruiter peptides derived from any of these other nuclear hormone receptor cofactors may be similarly prepared and assayed according to known procedures.